The present invention relates generally to medical technology and in particular aspects to methods and systems for addressing fistulae and other passageways and openings in the body. As further background, there exist a variety of passageways and openings in the body which can be plugged, blocked or otherwise occupied by medical implants and materials to provide benefit to the patient. For example, it may be desirable to plug or otherwise treat a fistula. A variety of fistulae can occur in humans. These fistulae can occur for a variety of reasons, such as but not limited to, as a congenital defect, as a result of inflammatory bowel disease, such as Chron's disease, irradiation, trauma, such as childbirth, or as a side effect from a surgical procedure. Further, several different types of fistulae can occur, for example, urethro-vaginal fistulae, vesico-vaginal fistulae, tracheo-esophageal fistulae, gastro-cutaneous fistulae, and any number of anorectal fistulae, such as recto-vaginal fistula, recto-vesical fistulae, recto-urethral fistulae, or recto-prostatic fistulae.
Anorectal fistulae can result from infection in the anal glands, which are located around the circumference of the distal anal canal that forms the anatomic landmark known as the dentate line. Approximately 20-40 such glands are found in humans. Infection in an anal gland can result in an abscess. This abscess then can track through soft tissues (e.g., through or around the sphincter muscles) into the perianal skin, where it drains either spontaneously or surgically. The resulting void through soft tissue is known as a fistula. The internal or inner opening of the fistula, usually located at or near the dentate line, is known as the primary opening. Any external or outer openings, which are usually located in the perianal skin, are known as secondary openings.
A gastrointestinal fistula is an abnormal passage that leaks contents of the stomach or the intestine (small or large bowel) to other organs, usually other parts of the intestine or the skin. For example, gastrojejunocolic fistulae include both enterocutaneous fistulae (those occurring between the skin surface and the intestine, namely the duodenum, the jejunum, and the ileum) and gastric fistulae (those occurring between the stomach and skin surface). Another type of fistula occurring in the gastrointestinal tract is an enteroenteral fistula, which refers to a fistula occurring between two parts of the intestine. Gastrointestinal fistulae can result in malnutrition and dehydration depending on their location in the gastrointestinal tract. They can also be a source of skin problems and infection. The majority of these types of fistulae are the result of surgery (e.g., bowel surgery), although sometimes they can develop spontaneously or from trauma, especially penetrating traumas such as stab wounds or gunshot wounds. Inflammatory processes, such as infection or inflammatory bowel disease (Crohn's disease), may also cause gastrointestinal fistulae. In fact, Crohn's disease is the most common primary bowel disease leading to enterocutaneous fistulae, and surgical treatment may be difficult because additional enterocutaneous fistulae develop in many of these patients postoperatively.
When surgery is deemed necessary, one operation for fistula closure is resection of the fistula-bearing segment and primary end-to-end anastamosis. The anastomosis may be reinforced by greater omentum or a serosal patch from adjacent small bowel. Still other methods for treating fistulae involve injecting sclerosant or sealant (e.g., collagen or fibrin glue) into the tract of the fistula to block the fistula. Closure of a fistula using a sealant is typically performed as a two-stage procedure, including a first-stage seton placement and injection of the fibrin glue several weeks later. This allows residual infection to resolve and to allow the fistula tract to “mature” prior to injecting a sealant. If sealant or sclerosant were injected as a one-stage procedure, into an “unprepared” or infected fistula, this may cause a flare-up of the infection and even further abscess formation.
There remain needs for improved and/or alternative devices and methods for addressing fistulae and other passageways and openings in the body. The present invention is addressed to those needs.